1. Field of the Invention
The invention is in the field of electronics and more specifically in the field of digital-to-analog converters.
2. Related Art
There are a variety of digital-to-analog converters. In one type of digital-to-analog converter a single capacitor is charged using a plurality of digitally switched current inputs. Each of the current inputs is configured to supply a share of a charging current. The amount of charging is dependent on the current or voltage sources, on the settings of the switches and, thus, the digital values used to control the switches. Charging is continued for a fixed time or until a threshold voltage is reached. For example, if the charging is continued for a fixed time then the resulting charge on the capacitor is used to produce an analog voltage or current.
The accuracy of this type of digital-to-analog converter is, in part, dependant on the accuracy of the current or voltage sources and/or timing elements. The precision of this type of digital-to-analog converter is dependant, in part, on the number of current input switches and/or the length of the measured time period.